Process of preserving organic materials.



UNITED STATES PATENT OFFICE.

HENRI monsnun, or ANGLEUR-LEZ-LIEGE, BELGiUM.

PROCESS OF PRESERVING ORGANIC MATERIALS.

No Drawing.

materials by means of solutions of metalliccompounds and notably of ammoniaca-l solutions, have several serious drawbacks. For instance, when solutions containing copper are brought into the presence of iron, the copper is precipitated and the oxygen and the acids which are released attack and corrode the iron. Solutions containing metallic salts have alsothe disadvantage of rendering the wood a good conductor of electricity. Further, when the salts c0mposing the solutions are formed of powerful acids, such as sulfuric acid and hydrochloric acid, these are released owing to the .combination of the metallic oxids with the constituents of the .wood, and are forced, together with a part of the ammonia, into the center of the wood. The part of the wood in which the metallic oxid is absent is attacked by the said acids and by the nitrous acids produced by the decomposition of the am.- monia. Another disadvantage of the solution of metallic salts is that, when these solutions are used for certain materials, or

cent-ration, the whole of the salts,.in the first case, and a part of salts in the second case, remain in a form soluble in water and are washed out of the prepared materials.

. The present invention has for its object to obviate these disadvantages 'by adding to the ammoniacal solution of a metal, phenic acid or its equivalents which have no deleterious action on the fiber of the wood, nor on iron, render the wood a bad conductor of electricity, neutralize the nitrous and nitric acids and prevent their format-ion.

\Vhen the phenols are added to the ammoniacal solution of metal, they combine in an insoluble and non-volatile manner, which is very advantageous, as their powerful antiseptic action is limited by their solubility or their volatility. Phenic acid has a fur- Specification of Letters Patent.

' Application filed October 26; 1911. Serial No. 656,900.

'tricity.

Patented Mar. 25, 1913.

ther advantage over the other-acids, in that it ermits the formation of metallic salts which are always insoluble in water after the alkali has disappeared, while in this same mixture, the other acids retain the greater part of the alkali to form metallic ammoniacal salts which are soluble in water when not combined with the vegetal material. This eflect is of the greatest importance in that itproduces impregnating solutions and coatings whichare always in-.

soluble in water no matter what may be the concentration of the solution. The addition of gum arabic or its equivalents also prevents oxidation by the solution and nullifies the conductivity of the metallic solutions. Oxidation may be further avoided by adding non-oxidizing acids, such as formic acid, oxalic acid, lactic acid, boric acid, etc., or by adding in suitable proportions oxidizing acids, such as hydrofluoric acid, etc, which, in the presence of the ammoniacal metallic solutions, have no corroding action on iron.

The following example will illustrate the solutions which may be used in accordance with this process':(1) 5% 011., 3%% Zn., 15% C H OH (phenic acid), 60% NH, (liquid ammonia 22 deg. B., 16 H 0. (2) 5% 011., 3% Zn., 5% 0 H, H, 10% COJ-I (formic acid), 60% NH, 16%% -H,O. when they are used in relatively strong con- Among the equivalents of the carbolic acid, weunderstand all the acid derivatives or derivatives soluble in the ammoniates of the aromatic series having no corroding action on iron.

Having ;now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

1. A process of preserving organic material which consists in impregnating the material in an ammoniacal solution of a metal to which has been added a non-oxidizing substance which is a non-conductor of elec- 2. A processof preserving organic mate- .rial which consists in impregnating the material in an ammoniacal solution of a metal to WhlCh has been added' a non-oxldlzmg snbstance which is a non-conductor of elec- In testimony whereof I have signed my tricity and an acid which is free from cor name to this specification in the presence of roding action on iron. two subscribing witnesses.

' 3. A process of preserving organic mate- HENRI MONSEUR. 5 rial which consists in impregnatmg the ma- Witnesses:

terial in an ammoniacal solution of a metal CHAS. -ROY NASMITH,

. to which has been added a phenol. EMILE VEBNMARELLI. 

